42 IL-6 as prognostic factor in adjuvant or metastatic skin cancer patients treated with immunotherapy – a deep biomarker analysis by Francesca Sparano, Corrado Caracò, Ester Simeone, Lucia Festino, Alfredo Budillon, Domenico Mallardo, Vito Vanella, Ernesta Cavalcanti, Paolo Ascierto, Claudia Trojaniello, Maria Grazia Vitale, Grazia D’Angelo, Marilena Tuffanelli, Sergio Arpino, Anita Minopoli, Mario Mallardo, Eleonora Cioli, Benedetta Alfano